(a) Field of the Invention
The present invention relates to a hollow golf club head such as so-called "metal wood", which is provided by integrally combining a plurality of crusts.
(b) Description of Prior Art
One of the representative of conventional hollow golf club heads is proposed in Japanese Utility Model Publication No. 61-33972, of which the FIG. 1 shows a golf club head comprising three crusts,i.e., a face crust, an upper crust and a sole and side-peripheral crust to be integrally combined, thus optionally adjusting a position of the center of gravity of a golf club head.
According to the conventional golf club head, however, there has been a problem such that in the event of using iron as materal of the crusts, comparatively a large specific gravity of iron has prevented the enlarging of the bulk or volume of the head body within a specified value, thus disenabling the elongating of a distance between the center of gravity of a head body and its face, so that so-called sweet area on the face cannot be sufficiently enlarged.
One of a means for solving the above problem may be, for example, a lost wax process in which fused light metal such as titanium or titanium alloy melt is poured into a mold to form each crust. However, such process is relatively inferior in the strength of each crust, thus preventing the enlarging of a volume of a golf club head.